Velvet Drive Leak After Coupling Disconnected

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JohnV8r
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Velvet Drive Leak After Coupling Disconnected

Post by JohnV8r »

Hey Guys,

I had to pull the coupling/shaft off my Velvet Drive transmissions to install PSS Dripless Shaft Seals. Starboard coupling was particularly sticky and I had to use a sliding impact hammer attached to the end of the shaft AND the socket trick to get it off. That was four - five weeks ago. Still on the hard yesterday and noticed a very small amount of transmission fluid in the bilge under the area where the coupling connects (low spot on tranny).

Dipstick shows transmission is right on the line for transmission fluid, so not a major amount has leaked.

Is it possible some transmission fluid got around a seal while the coupling was being removed and the fluid has just found its way to the bilge or is this an indication of a larger problem? The transmissions had not been rotated around for months while I've been on the hard.

I'm about to launch, so I'm trying to decide if this is a big enough issue that I need to delay.

Thanks,

JohnV8r
Bertram 31 - The Best Boat Ever Built
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Bruce
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Re: Velvet Drive Leak After Coupling Disconnected

Post by Bruce »

Seals get old and dry out or the internal coil spring around the lip of the seal breaks and the seal lip is not as tight on the output shaft.
A slide hammer on the shaft still attached to trans output shaft shocks and that internal lip spring can come off.

Might want to change seal while out of the water. .
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JohnV8r
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Re: Velvet Drive Leak After Coupling Disconnected

Post by JohnV8r »

Thanks Bruce!
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Carl
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Re: Velvet Drive Leak After Coupling Disconnected

Post by Carl »

What Bruce said.

...in addition, a lip seal over time can wear a narrow, shallow groove(and sometimes not so shallow) in the transmission coupling.
The rubber seal with spring rides in the groove sealing just fine. With the coupling spinning in and out of gear and under pressure the seal just rides the groove like a train on tracks.

Slap hammer can pull the transmission coupling out just enough so the seal is no longer riding perfectly in its little happy spot and you'll get a small leak.
It may just be a drop or two that gets past the seal before the seal finds its way back home. Or a few rotations bring it back like installing a belt on a pully.
But as Bruce said...some age may not have that seal as soft and pliable as it once was.

In short...changing seal like Bruce said is a good idea... and while you have the transmission coupling off, check for a groove on the trans coupling where seal rides. If no groove, no worries. Slight you have the option of leaving as is or polish with fine emery cloth or buying a new one. Pitted with a heavy groove you have little choice but to have machined for a sleeve or buy new.

But its a drip or drop from your words, most likely a seal change is already overkilling and your good as new.
Just one of those things to check while its apart.
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JohnV8r
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Re: Velvet Drive Leak After Coupling Disconnected

Post by JohnV8r »

Thanks Carl!
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JohnV8r
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Re: Velvet Drive Leak After Coupling Disconnected

Post by JohnV8r »

Hey Guys,

This is what I am able to find on the internet for parts. I just want to confirm this covers what I'll need based on your comments above.

"Borg Warner Velvet Drive Gasket and Seal Kit Complete gasket and seal kit for Borg Warner Velvet Drive 71 and 72 series transmissions"

https://www.amazon.com/Velvet-Transmiss ... B00FFD5SZY

Thanks,

JohnV8r
Bertram 31 - The Best Boat Ever Built
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Carl
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Re: Velvet Drive Leak After Coupling Disconnected

Post by Carl »

Personally I'd take the number and or sizes from the seal then call my local Bearing House, give them the information and just buy the one I need.
Maybe I'd buy a spare for the other side as insurance that it will never leak.
Seal might be $5.00-$10.00.
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Rawleigh
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Re: Velvet Drive Leak After Coupling Disconnected

Post by Rawleigh »

Carl: Do you think a Speedi sleeve would work if the shaft has a groove in it?
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Carl
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Re: Velvet Drive Leak After Coupling Disconnected

Post by Carl »

I'm not a fan of stretching a seal so far over its intended size, that said I'm sure they would work.

With hard to get couplings or customers in a rush we used to turn down the diameter then make a press-fit sleeve keeping the original specs on the diameter.
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